Dental practitioners generally make assessments of clinical problems in a patient's oral cavity based on visual inspection and personal knowledge. However, small changes to tooth and/or gum surfaces can have clinical importance, and it can be difficult for the dental practitioner to identify such small changes. Additionally, the magnitude and rate of change to a patient's dentition may not be easily determined. For example, the dental practitioner may have difficulty in determining the specific, subtle changes that might have occurred to the patient's dentition.
Intraoral scanners are a useful tool in dentistry and orthodontics. However, intraoral scans are not generally used for longitudinal analysis. One reason is that the results of intraoral scans performed by intraoral scanners include errors introduced by the intraoral scanners, which makes comparison between images difficult and error prone.